Process of making glass articles having antireflective coatings and product

Abstract

Disclosed is a process of making a glass article containing a thin surface film antireflective coating made by providing a dispersion containing at least one metalloorganic compound in solution, depositing a thin coating of such dispersion on the glass substrate, heating the film to drive off the solvent and to decompose the organic components, thus forming a glass film from the remaining inorganic oxide components, further heating the glass film layer to cause phase separation thereof, and thereafter etching and leaching such film to dissolve out preferentially one of the phases of the phase-separated glass, leaving a skeletonized surface film having a graded refractive index; and products resulting from such process.

We claim: 
     
       1. A process of making a glass article containing a thin surface film antireflective coating which comprises (1) providing a dispersion of organic derivatives of more than one inorganic cation, said dispersion containing at least one metallo-organic compound in solution in a liquid solvent, the components of said dispersion being capable of decomposition and reaction together under the influence of heat to form an inorganic oxide glass capable of phase separation into two immiscible phases on further heating,   (2) depositing a thin coating of such dispersion on the glass article, heating the coating to drive off the solvent and to decompose the organic components, thus forming a glass film layer from the remaining inorganic oxide components, further heating the glass film layer to cause phase separation thereof into to immiscible phases, and thereafter etching and leaching such film to dissolve out preferentially one of the phases of the phase separated glass, leaving a skeletonized surface film having a graded refractive index.   
     
     
       2. A process according to claim 1 wherein the phase separated glass film layer is less than 0.5 mm thick. 
     
     
       3. A process according to claim 2 wherein the said glass film layer is less than 0.1 mm thick. 
     
     
       4. A process according to claim 1 wherein the said phase separated glass film layer is less than 1 micron thick. 
     
     
       5. A process of claim 2 wherein the thickness of said skeletonized surface film is less than that of the total glass film applied to the surface of said glass article according to said process. 
     
     
       6. A process of claim 3 wherein the thickness of said skeletonized surface film is less than that of the total glass film applied to the surface of said glass article according to said process. 
     
     
       7. A process of claim 4 wherein the thickness of said skeletonized surface film is less than that of the total glass film applied to the surface of said glass article according to said process. 
     
     
       8. A product of the process of claim 1 wherein the inorganic oxide glass of paragraph (1) has a composition different than the glass article of paragraph (2). 
     
     
       9. A product of the process of claim 7 wherein the inorganic oxide glass of paragraph (1) has a composition different than glass article of paragraph (2). 
     
     
       10. A process which comprises (1) providing a glass article and abrasively polishing at least one surface of said glass article,   (2) providing a dispersion of organic derivatives of more than one inorganic cation, said dispersion containing at least one metallo-organic compound in solution in a liquid solvent, the components of said dispersion being capable of decomposition and reaction together under the influence of heat to form an inorganic oxide glass capable of phase separation into two immiscible phases on further heating,   (3) depositing a thin coating of such dispersion on the glass article, heating the coating to drive off the solvent and to decompose the organic components, thus forming a glass film layer from the remaining inorganic oxide components, further heating the glass film layer to cause phase separation thereof into two immiscible phases, and thereafter etching and leaching such film to dissolve out preferentially one of the phases of the phase separated glass, leaving a skeletonized surface film having a graded refractive index,   thus providing a glass article having an antireflective surface coating, and wherein the inevitable scratches on said base glass resulting from abrasive polishing are healed during the formation of the coating thereon of a phase-separable glass film layer.